DENVER – Hurricane forecaster William Gray is still predicting a slightly above-average hurricane season.
The Colorado State University scientist said in his team's final forecast for the 2001 season that data indicate there will be 12 named storms and seven hurricanes, with three of them major or intense.
"We think this year will be somewhat in keeping with five of the last six seasons (1997 is the exception), though it will be less active than any of the others," Gray said. "We will see above-average activity, especially compared with the long-term downturn in activity experienced during the quarter-century period of 1970-94."
Gray said, "These numbers aren't extreme, but they continue the trend in which hurricane activity appears to be on a multi-decadal upswing."
The team, in its December forecast, called for an average- or slightly below-average season, which runs from June through November.
That was revised up in both the April and June revisions. The final forecast is consistent with the June 7 update when the team became convinced there would be no significant El Nino event to inhibit Atlantic Basin hurricanes.
The long-term (1950-90) average for seasonal activity includes 9.3 named storms, 5.8 hurricanes and 2.2 intense hurricanes.
The Colorado State team says there are a number of reasons for the expected slight increase. Chief among these are warmer-than-normal Atlantic sea surface temperatures, expected lower-than-average tropical Atlantic surface pressure and the lack of a significant El Nino event.
As of Aug. 6, only two of the 12 predicted storms have appeared: Tropical Storm Allison, which brought heavy rains to Texas in June, and Tropical Storm Barry, which crossed the western Florida Panhandle early Monday.
"A slow or fast start to the season isn't unusual," Gray said. The peak time for storm formation typically "ramps up" from about Aug. 20 to a peak around Sept. 10 and then "ramps down" sharply to infrequent formation after Oct. 20.
Chances for U.S. landfall of at least one major storm with at least 110-mph winds are higher than average this year.
The forecast estimates the probability of one or more Saffir-Simpson category 3-5 hurricanes making landfall somewhere on the U.S. coast during 2001 as 69 percent. Storms in those categories can do extensive damage. The average for the past century is 52 percent.
The landfall probability for the U.S. East Coast and Florida peninsula is 50 percent, compared with the average of 31. For the Gulf Coast from the Florida Panhandle westward to Brownsville, Texas, the major hurricane landfall probability is 39 percent compared with an annual average value of 30 percent.